Overcurrent protection device for semiconductor device

An overcurrent protection device for a semiconductor device, comprising:

• a current detection circuit configured to detect, as a sense voltage, a sense current flowing through a current sense terminal of the semiconductor device;
• an overcurrent detection circuit configured to compare the sense voltage detected by the current detection circuit with an overcurrent threshold value to output an overcurrent detection signal;
• a mode determination circuit configured to determine a superposition mode in which a transient sense voltage is superimposed on the sense voltage or a normal mode in which the transient sense voltage is not superimposed on the sense voltage;
• and
• a timing adjustment circuit configured to adjust a detection start timing of the overcurrent detection signal based on a result of the determination by the mode determination circuit, the timing adjustment circuit including a first delay circuit configured to set a first false detection prevention period to the overcurrent detection signal when the result of the determination of the mode determination circuit indicates the superposition mode and a second delay circuit configured to set a second false detection prevention period shorter than the first false detection prevention period to the overcurrent detection signal when the result of the determination of the mode determination circuit indicates the normal mode.

An overcurrent protection device for a semiconductor device, comprising:

• a current detection circuit configured to detect, as a sense voltage, a sense current flowing through a current sense terminal of the semiconductor device;
• an overcurrent detection circuit configured to compare the sense voltage detected by the current detection circuit with an overcurrent threshold value to output an overcurrent detection signal;
• a mode determination circuit configured to determine a superposition mode in which a transient sense voltage is superimposed on the sense voltage or a normal mode in which the transient sense voltage is not superimposed on the sense voltage, and to output a mode determination signal based on a result of the determination of the superposition mode or the normal mode;
• and
• a timing adjustment circuit, connected to the overcurrent detection circuit and the mode determination circuit, configured to adjust a detection start timing of the overcurrent detection signal based on the mode determination signal which is output by the mode determination circuit to the timing adjustment circuit and the overcurrent detection signal which is output by the overcurrent detection circuit to the timing adjustment circuit.